Control method and apparatus



Ju'ly 6,1943. H. A. RICKTT 2,323,876

CONTROL METHOD AND APPARATUS Filed May 31, 1941 cooLf/i /0 I I I l I l I I l CONTROL MEC//HN/JM -fif INVENTOR Patented July 6,. 1943 uNlTEp STATE s lm'llaN'l"v OFFICE GONTROL METHOD AND APPARATUS Henry A. Rickett, Riverside,

Socony-Vacuum Oil- Company B. I., assignor to Incorporated,

New York, N. I., a corporation of New 'York Application May 31, 1941, No. 395,970

' z claims. (m. isc-f4) This invention has to do with method end means for controlling' the degree ,of dehydrationl oflsgasolines. kerosenes and similar hydrocarbon i In United States Patent 2,195,989', to Edward L. Hoiman, there is disclosed a method of controlling the'internal corrosion of pipelines carrying light hydrocarbon o il products by removing from those oils, prior to transportation, the water dis-- solved in the oil to a suillcient extent to prevent its separation from the oil` while vpassing through the pipe.

water, and the cooling of such a solution, .in the quantities in which gasolines are handled in reflneries'and pipe lines, will precipitate an appreciable amount of water.

Returning to the drawing, it 'wili be remem- V bered 'the iinished dehydrated gasoline is flowing inpipe II. From this pipell ahy-pass pipe I2 is provided, leading through cooler I3 and pipe I l, which pipe AI4 is provided with transparentl ends, preferably of4 yoptically clear glass, at i5 and I6, and which pipe I4 is immersed-in a constant temperature bath I1., which bath is equipped with controls of the usual type. here omitted for simplicity. The by-passed oil stream isreturned. to pipe I I, through pipe I l and theentire by-pass may be isolated by cutoi! valves I9 and 20.

The method o f usual operation is as follows. If lthe dehydration is desired to be-so carried on -that the product oilcarries not more than a certain maximum amount of water, there is, of course, a certain .temperature level at which that amount of water will just saturate the oil, and

reference tothe drawing attached to this speciil'cation, the single figure of which shows, in dia*- gram form, both the apparatus for the detere mination ,or water and one'of the manners in which it may be used 'to control a dehydration' pily'eoess irl-:connection with which it may be opera In the drawing there is shown a dehydrator I which may be of any type but is usually a vessel 2 packed with an adsorbent dehydrating.

below which water willbe precipitated and form a haze in the oil. Ii the oil is beingdehydrated `1or purposes o! preventing pipe line corrosion,

as in the Hellman patent, it is desired that the. water be so reduced that none will separate if the oil is cooled to a-certain temperature. In either event, a critical temperature is associated 30. with the operation. fIn operation then, the conmaterial 3 such as activated alumina, .or-rock salt, supportedV upon a-grid l and through which oil to be dehydrated is introduced hypipe 5 and pipe B-controlled by valve 1, dehydrated oil leaving through' pipe); A convenient means of controlling degree oi dehydration is by dehydrat- Ving a major portion of the oil to a greater extent than required and by-passing a portion of undehydrated oilthrough pipe 9 under control II which has the desired amount or moisture;

It must be .emphasized here that this process about which we are speaking hasl nothing to do wlththe separation of discrete water, such as breaking of emulsions, and the like, but'only with treatments for the removal of water completely dissolved in the oil. VAs pointed out in the HOH- man patent it is frequently not appreciated. that fairly considerable quantities of water may be present in optically clear solution when saturated, will contain about of valve lo to furnish a. nnalblend of oil in pipe stant temperature bath I1 is'held at that temperature which is.the dividing, line between optically clear and hazed oil for the' desired water concentration. In such operation the cooler I3 is merely utilized to perform the bulklor the tem-1 perature control, leaving to bath -II the'precise control, as is usual in such operations;

Then, a light source 2f .may be observed through the oil containedin time u, either visu.

some light remnsive device as, for

ally 0f bv l example'. photo-electric cell- 22. In either event. thel absence o i haze at the predetermined tem-- perature will indicate acceptably dehydrated oil,

and. the presence of haze atthat temperature will indicate insumelently treated oil. If .visually observed, manual control responsive thereto may` eiect control o! the dehydration,. as by adjustment of bypass valve III. or if observed electril cally a suitable I,control mechanism. 23 actuated responsively to the light incident upon cell 22 may be' utilized forcontrol of that valve I0. Sevin light oils.l For example, a gasoline of usual type at '70 F.,

0.0080%' of 55 note that by provision ora tube of suitable length,

eral-such mechanisms -may be worked out, and

their provisionV does not at this time constitute a pdrtion of this invention.. 1t is of interest to the difference between the light'transmitted by an optically clear solution and one containing even a slight haze may be quite marked.

Several methods for running dehydration of oils to produce iinal products of desired water content are noted in the Hotlfmann patent mentioned, and this control may be applied equally well to any.

While the bare method above described is merely an inspection of the pass-no pass type, a complete supervision to prevent over-dehydration can be accomplished bythe addition of a. second sight tube and constant temperature bath working at a temperature spaced from and below the temperature of the irst bath, in which c'ase an optically clear oil in the first sight tube indicates that enough dehydration is being practiced, while a hazed oil in the second tube gives the information that over-dehydration is not being practiced.

Equally well, with a light intensity responsive device at 22, so connected as to indicate at 24 the intensity of the light falling thereon, the bath temperature may be so chosenl as to create a desired intensity of haze with oil of a given water content. Then, greater light transmission than that corresponding to this desired haze intensity indicates over dehydration, and lower light transmission indicates underdehydration. In this setup the functioning of control 23 would be no different than before noted.

As in all such mechanisms of this general class, the light source 2| must be one of the many forms of constant intensity light source usually provided for similar duties.

I claim:

1. Apparatus for control of the degree of dehydration of an oil containing dissolved water comprising an agency capable of reducing the amount of dissolved water to a variable degree, a sight tube through which at least a portion of the dehydrated product from such agency is passed, a constant temperature bath surrounding said sight tube, means for holding said bath at a predetermined temperature, a constant intensity light source at one end of said sight tube, light-intensity responsive means at the other end of said sight tube, and means to control the variably operating dehydrating agency in response to the intensity of transmitted light at the predetermined temperature.

2. A method for the control of a dehydrating apparatus which is removing dissolved water from oil comprising the steps` of passing at least a portion of the dehydrated oil through a sight tube at a temperature adjacent the saturation temperature corresponding to the desired water content, passing a light beam of constant intensity through said sight tube, observing the comparative light transmission through the oil in said tube as iniiuenced by the presence, absence, or degree of haze at the predetermined temperature, and varying the operation of the dehydrator in response to said comparative light transmission.

HENRY A. RICKEI'I. 

